The invention relates to a water closet with a gravity operated flush water system. More particularly, the invention is concerned with a water closet including a body portion with an upper level and a lower level, and integral with said body portion a closet bowl and an outlet conduit forming an odor seal at the bottom of said bowl, said odor seal having an outlet crest determining the highest water level of said odor seal, further a flush water container adjacent to said body portion and means for flushing said closet bowl by means of water passing by gravity from said flush water container through said bowl and said outlet conduit.
One object of the invention is to create a novel water closet design having siphon flushing and a low flush water consumption. Siphon flushing means that the flushing fills the outlet conduit downstream of the odor seal with water so that the outlet functions like a siphon and sucks the water out from the bowl and the odor seal due to gravity acting on the water filling a downwards directed portion of the outlet conduit, This gives a very effective flushing but known water closets with this kind of flushing have a very great flush water consumption and also a very complicated design of the outlet conduit which makes the manufacture of the water closet difficult and expensive. Known water closet of this type are shown, for example, in U.S. Pat. Nos. 3,224,013 and 2,116,528.